Exemplary embodiments of the invention relate to a method for controlling an actuator that is connected to an operating element of a manual user interface, and that serves for the output of a haptic feedback signal SA(t) to the user via the operating element. Furthermore, exemplary embodiments of the invention relate to a manual user interface comprising an operating element for the manual input by a user and an actuator connected to the operating element for the output of a haptic feedback signal SA(t) to the user via the operating element.
Exemplary embodiments of the invention are used with any manual user interfaces that are formed for the output of a haptic feedback signal, wherein the haptic feedback signal specifies, in particular, information about a current state of the manual user interface or the operating element. Here, the manual operating elements can be, for example, a button, a touch-sensitive surface, a switch, a computer mouse, a joystick, etc.
European patent document EP 2 117 122 A1 discloses an arrangement and a method for haptic and/or acoustic feedback to sensory operating elements. The arrangement for the feedback of the actuation to sensory operating elements comprises at least one carrier plate as the operating element, a sensor arranged on the carrier plate, at least one broadband electro-mechanic and/or electro-acoustic signal transducer, preferably a voice coil that is allocated to the at least one carrier plate, and a control unit electrically connected to the sensor and the voice coil and is set up to analyze the sensor signals emitted by the sensor and for the generation of at least one haptic and/or acoustic feedback signal.
The term “haptic user interface” is also used for such arrangements as are disclosed in EP 2 117 122 A1. Such “haptic user interfaces” enable a user to obtain tactile or kinetic feedback at the same time as manually actuating the operating element. This feedback allows the creation of an intuitive connection between the manual actuation of the operating element and the actions induced thereby. Furthermore, this feedback enables the user to be informed, for example, about a current state or mode of the operating element, without a display having to be observed. This is particularly advantageous when the operating element is arranged in a vehicle, in particular a motor vehicle, and controls motor vehicle systems, for example. During operation, the driver does not have to turn his/her attention away from the observation of the surrounding traffic situation and towards the operating element in order to obtain information about the current state of the haptic user interface or the operating element, but rather he/she obtains this information about the current state of the operating element via the haptic feedback. Thus, a user can recognize, by means of the emitted feedback, for example, when a switching process generated by an input into the operating element is carried out. In particular, feedback signals can be depicted that represent different pieces of information, for example a first feedback signal that represents a correctly recognized actuation of the operating element and a second feedback signal that represents an erroneous input in the event of the actuation of the operating element. In particular, the haptic impression in the event of the actuation of a button, for example, can thus be approximately simulated.
Furthermore, feedback signals can signalize the correctly recognized start of an actuation of the operating element and the correctly recognized end of an actuation of the operating element. This is always advantageous when it is an input of a time interval. In these cases, the output of a first feedback signal takes place advantageously as soon as the start of the actuation has been correctly recognized, and the output of a second feedback signal takes place as soon as the end of the actuation has been correctly recognized.
Embodiments of the invention are directed to an improved haptic user interface and a method for controlling such a haptic user feedback interface that takes a user-specific operation of the operating element into consideration.
A first aspect of the invention involves a method for controlling an actuator connected to an operating element of a manual user interface and serves for the output of a haptic feedback signal SA(t) to a user via the operating element. A sensor is present in the operating element, the sensor detecting a sensor signal SS(t) generated by a manual input of the user as a reaction to the emitted feedback signal SA(t). The method comprises the following steps:
In one step, after output of a feedback signal SA(t0) at a time t0, a determination of a reaction time RZ of the user is carried out by the actuator on the basis of the sensor signal SS(t) for t>t0, wherein, if the determined reaction time RZ is shorter than a predetermined limit value GRZ, haptic feedback signals SA(t) to be emitted in the future are changed in such a way that their haptically perceptible (by a user) intensity is reduced, and, if the determined reaction time RZ is greater than a predetermined limit value GRZ, haptic feedback signals SA(t) to be emitted in the future are changed in such a way that their haptically perceptible (by a user) intensity is increased.
In an alternative or additional step, after output of a feedback signal SA(t0) at a time t0, a determination of a maximum magnitude |SS(t)|max of the sensor signal SS(t) is carried out by the actuator on the basis of the sensor signal SS(t) for t>t0, wherein, if the determined maximum magnitude |SS(t)|max is lower than a predetermined limit value GSsmax, haptic feedback signals SA(t) to be emitted in the future are changed in such a way that their haptically perceptible (by a user) intensity is reduced, and, if the determined maximum magnitude |SS(t)|max is greater than a predetermined limit value GSsmax, haptic feedback signals SA(t) to be emitted in the future are changed in such a way that their haptically perceptible (by a user) intensity is increased.
The term “operating elements” is presently understood as being broadly defined. Such an operating element forms the interface that receives a manual input of a user and detects this as sensor signals SS(t) with the sensor. To do so, the sensor is suitably connected to the operating element. The manual input is advantageously generated by a force input, a moment input, or a pressure input of the user in or on the operating element. Touch-sensitive surface elements, such as known from touch pads, for example, buttons, switches, computer mice, joysticks, etc. fall under the term “operating element”.
In general, all sensors that are implemented for the detection of a manual input can be considered, in particular force sensors, pressure sensors, moment sensors or a combination thereof. In the event of the manual input of a user on the operating element, the sensor detects time-dependent time signals SS(t). These sensor signals SS(t) preferably reproduce forces and/or moments and/or pressures that the user applies to the operating element during the input. In particular, the sensor signals SS(t) can be multi-dimensional, and thus specify multi-dimensional states of the operating element, for example positions, angles, speeds, accelerations of the operating element.
The term “actuator” is presently understood as being broadly defined. For example, electric motors, piezoelectric elements, voice coils, hub magnets, etc. fall under this. The actuator serves to generate a feedback signal SA(t) on the operating element that can be haptically perceived by the user. Advantageously, the feedback signal SA(t) can be predetermined or set in terms of its amplitude or its amplitude response, its frequency or its frequency response, its subsiding behavior. One or more temporally successive feedback signals SA(t) signalize to the user, for example, that the manual input carried out led to a change of the state of the operating element because of its input intensity and/or temporal length, for example the operating element adopted or generated a new switching state, and/or the feedback signals SA(t) facilitate the start and the end of a manual input into the operating element to the user.
The proposed method automatically adapts the haptic feedback signals SA(t) to input characteristics of the respective user, such that it is individually ensured for each user that he safely and reliably perceives emitted feedback signals SA(t0).
Advantageously, the feedback signals SA(t) that are determined in such a way and are adapted to the respective user can be stored in a retrievable manner. Advantageously, a user interface, which has at least one such operating element, is initiated specifically for the respective user. Thus, it can be ensured that, if several users come into question for inputs into the operating element, the feedback signals SA(t) optimized for each user are emitted for them.
According to a first alternative of the method, this is achieved by a reaction time RZ of the user being determined after output of a feedback signal SA(t0) at the time t0 by the actuator on the basis of the detected sensor signal SS(t) for t>t0. Advantageously, the reaction time RZ is determined starting from to in a predetermined time interval. To do so, the sensor signal SS(t) is advantageously analyzed for t>t0. For example, the reaction time RZ can be the time that passes from the time t0 to reaching a maximum or minimum of the sensor signal SS(t) for t>t0. The criteria for determining the reaction time RZ can be chosen deviating therefrom, corresponding to the task. The reaction time RZ is hence the time that has passed since the output of the feedback signal SA(t0) at the time t0, until a reaction of the user triggered thereby is carried out, which can be recognized by means of the sensor signal SS(t) for t>t0.
According to the definition of the reaction time RZ, a limit value GRZ is predetermined that advantageously defines a normal reaction time that can be expected. The limit value GRZ is correspondingly predetermined depending on the specification and task. Advantageously, the limit value GRZ is chosen from the range 20 to 60 ms or from the range 30 to 50 ms. If the determined reaction time RZ is shorter than the predetermined limit value GRZ, then the haptically perceptible intensity of the emitted feedback signal SA(t) is selected too high, such that, in this case, haptic feedback signals SA(t) to be emitted in the future are automatically changed in such a way that their haptically perceptible intensity is reduced.
Whereas, if the determined reaction time RZ is greater than the predetermined limit value GRZ, then it can be assumed from this that the feedback signal SA(t0) was not perceived or not correctly perceived by the user. As a reaction, haptic feedback signals SA(t) to be emitted in the future are automatically changed in such a way that their haptically perceptible intensity is increased.
In a second alternative or in addition to the first alternative, a maximum magnitude |SS(t)|max of the sensor signal SS(t) is determined after output of a feedback signal SA(t0) at the time t0 by the actuator on the basis of the sensor signal SS(t) for t>t0. Advantageously, the maximum magnitude |SS(t)|max is determined starting from to in a predetermined time interval. Furthermore, a limit value GSsmax is predetermined that advantageously defines a normal maximum magnitude |SS(t)|max of the sensor signal SS(t) that can be expected. The limit value GSsmax is correspondingly predetermined depending on the specification and task.
If the determined maximum magnitude |SS(t)|max is lower than the predetermined limit value GSsmax, then it can be assumed that the feedback signal SA(t0) at the time t0 was extraordinarily well perceived by the user. A haptic feedback signal SA(t) to be emitted in the future can thus be automatically changed in such a way that its haptically perceptible intensity is reduced in comparison to the previous feedback signal SA(t0) at the time t0. Whereas, if the determined maximum magnitude |SS(t)|max is greater than the predetermined limit value GSsmax, then haptic feedback signals SA(t) to be emitted in the future are automatically changed in such a way that their haptically perceptible intensity is increased.
Advantageously, the haptic feedback signals SA(t) to be emitted in the future are correspondingly changed in a predetermined intensity step. The method is then advantageously carried out again in the event of an output of the changed feedback signal SA(t), such that a continuous optimization to the respective user takes place. Advantageously, a change of the feedback signal SA(t) is carried out depending on the detected sensor signal SS(t) for t>t0 and/or a determined deviation of the reaction time RZ emerging from the sensor signal SS(t) for t>t0 from the limit value GRZ and/or a determined deviation of the maximum magnitude |SS(t)|max emerging from the sensor signal SS(t) for t>t0 from the limit value GSsmax′.
The haptically perceptible intensity of the haptic feedback signals to be emitted can be reduced or increased by various measures. For example, the feedback signal SA(t) can be changed in terms of its amplitude/its amplitude spectrum and/or its frequency/its frequency spectrum and/or its temporal increase or decrease behavior and/or its attenuation behavior.
If, in the event of an input of the user on the operating element, two or more temporally successive feedback signals SA(t) are emitted in order to thus signalize different switching states of the operating element to the user, the previously described method is advantageously implemented for each of the emitted feedback signals SA(t01), SA(t02), SA(t03) etc. Thus, by analyzing the sensor signals SS(t) following the respective feedback signals SA(t), two or more determined reaction times RZ01, RZ02, RZ03 . . . and two or more maximum magnitudes |SS,01(t)|max, |SS,02(t)|max, |SS,03(t)|max, . . . emerge. Advantageously, the average of these is respectively taken and they are compared to the limit values GRZ or GSsmax. Based on this comparison, the haptic feedback signals to be emitted in the future are changed, so to speak, as described above. Alternatively to this, only the sensor signals SS(t) that are detected temporally after output of a feedback signal SA(t01), SA(t02), SA(t03), . . . can also be analyzed as stated above, wherein all haptic feedback signals SA(t) to be emitted in the future can be changed based on this, as described above.
The proposed method is advantageously only implemented after the request of a user. This request can take place in a corresponding input interface as a result of a manual or acoustic input. In this case, the previously described adjustment of the feedback signals SA(t) is carried out after an explicit request of the respective user. Alternatively to this, the proposed method can take place automatically in the event of each manual input in the user interface.
A further aspect of the invention relates to a user interface comprising: an operating element for the manual input by a user, an actuator connected to the operating element for the output of a haptic feedback signal SA(t) to the user via the operating element, a sensor connected to the operating element, the sensor detecting a sensor signal SS(t) that is generated by a manual input of the user into the operating element as a reaction to the emitted feedback signal SA(t), and a control apparatus connected to the actuator and the sensor.
The control apparatus is implemented and set up in such a way that, after output of a feedback signal SA(t0) at a time t0, a reaction time RZ of the user is determined on the basis of the sensor signal SS(t) for t>t0, wherein, if the determined reaction time RZ is shorter than a predetermined limit value GRZ, haptic feedback signals SA(t) to be emitted in the future are changed in such a way that their haptically perceptible (by a user) intensity is reduced, and, if the determined reaction time RZ is greater than a predetermined limit value GRZ, haptic feedback signals SA(t) to be emitted in the future are changed in such a way that their haptically perceptible (by a user) intensity is increased, and/or after output of a feedback signal SA(t0) at a time t0, a maximum magnitude |SS(t)|max of the sensor signal SS(t) is determined on the basis of the sensor signal SS(t) for t>t0, wherein, if the determined maximum magnitude |SS(t)|max is lower than a predetermined limit value GSsmax, haptic feedback signals SA(t) to be emitted in the future are changed in such a way that their haptically perceptible (by a user) intensity is reduced, and, if the determined maximum magnitude |SS(t)|max is greater than a predetermined limit value GSsmax, haptic feedback signals SA(t) to be emitted in the future are changed in such a way that their haptically perceptible (by a user) intensity is increased. The control apparatus advantageously comprises a processor and a storage unit.
Advantages and preferred developments of the proposed user interface emerge by the corresponding and analogous transferral of the embodiments produced in conjunction with the proposed method.
A further aspect of the invention relates to a vehicle having a user interface, as described above.